Air conditioning system is an apparatus in which a refrigerant performs a refrigerant cycle including compression, condensation, expansion, and evaporation, in order to control the temperature of certain space according to user's desire. When the air conditioning system is operated to lower the temperature of the certain space, the air conditioning system is used as a cooling system. On the other hand, when the air conditioning system is operated to increase the temperature of the certain space, the air conditioning system is used as a heat pump. Meanwhile, the air conditioning system is usually used as the cooling system. The air conditioning system includes an indoor unit and an outdoor unit. The indoor unit is located in a humanly occupied space to supply a cool air thereto, and the outdoor unit is located at an outside of the humanly occupied space to release heat.
Further, the indoor unit includes a heat exchanger extracting heat from the humanly occupied space, a blower fan forcibly blowing an air to the heat exchanger to create a convective heat transfer therebetween for a fast supply of a cool air to the humanly occupied space. There are several kinds of indoor units such as a wall mount, a standing, a ceiling-suspended and a ceiling-embedded types according to the installation method of the indoor unit.
Typically, the wall mount type indoor unit is fixed to a wall of a room, and includes an air suction hole at an upper side and an air discharge hole at a bottom. However, it is not good for the user to use the typical wall mount type indoor unit having the above-mentioned structure because the suction hole is formed at the upper side and the discharge hole is formed at the bottom. In detail, the drawback is that the air conditioning is not rapidly performed for an entire indoor space because the discharging air is blown only in downward direction.
Further, an inside construction of the indoor unit is limited. For example, since a cross flow fan is installed in the related art indoor unit, a flow rate is restricted and the indoor unit has a large size because the cross flow fan occupies a large portion of the indoor unit.